1. Field of the Invention
This invention concerns apparatus and a method of using same, which is applicable to oil wells where well pressure has developed. More specifically, it relates to an apparatus and method for retrieving a shooting valve or the like from a well under pressure, without killing the well.
2. Description of the Prior Art
Heretofore, a U.S. Pat. No. 3,830,304 issued Aug. 20, 1974, has indicated some apparatus and a procedure that could be used to isolate (with a pressure seal) a portion of the internal tubing connections in a well. However, it involved connection to the tubing, which connection had to be maintained in order to contain the pressure within that tubing. Furthermore, such pressure maintenance had to be above the surface valves on the well head. Consequently, what that patent purports to accomplish is the ability to contain the pressure from production tubing by inserting a tool through the well head valves, without the need for removing such valves.
In contrast, the applicants invention provides for the ability to hold the well pressure at the casing head, and then while so containing the well pressure remove any well head valve so that it may be used elsewhere. Thus, it is an object of this invention to provide a relatively simple tool which may be used for removing well head valves or the like, without the need for killing the well first.